Rock boring



Pressure O. SCHAUB ROCK BORING Filed July 9, 1923 Oct. 21 1924.

M. m W e .n m 5 e W Patented Oct. 21, 1924.

UNITED STATES OTTO SCHAUB, 0F WINTERTHUR, BWITmLAID.

ROCK BOBDG.

Application Med July 9, 1923. Serial Ho. 650,814.

To all whomI it may concern.'

Be it known that I, O'rro SCHAUB, a citizen of Switzerland, residing at Winterthur, Switzerland, Bankstrasse 3, have invented certain new and useful Im rovements in Rock Boring, of which the following is a specification.

The various procees and apparatus for deep boring known today all have the drawback of being complicated and therefore slow and costly; this drawback is removed by adopting the process and apparatus constituting the present invention.

According to this process bore-holes are constructed by introducing water at a highpressure into the hollow space between two vertical tubes arranged concentrically within each other, their lower ends being connected by a ring of blading similar to the guide wheel of a turbine, and by introducing an abrasive material into the inner of the two tubes, whereby this material is carried at a high speed in a tangential direction through the blading by the inwardly flowing pressure-water and thereby wearing out a tubular hollow by its abrasive action in the rock which is to be bored.

In contrast to the Danish wash-out method, with which the present process has most similarity and which is only adopted in sandy soil, which makes use of the scouring action of a water jet where water under high pressure issues from a nozzle, the abrasive action of the abrasive material is used in the present process, the material being set in circular motion by pressurewater, and this process is therefore suitable not only for sandy ground, but still more for boring the hardest rock.

The abrasive material adopted consists of a hard sand, for example, quartz, corundum, or carborundum sand, according to the hardness of the rock which is to be bored.

In order to avoid the apparatus becoming stopped upgand also to reduce the resistance to motion of the abrasive sand introduced into the inner tube, the sand is mixed with a soft clay paste, so that the abrasive medium can easily reach the boring position in a pasty condition.

The apparatus for carrying out the process consists of two vertical tubes arranged concentrically in each other, their lower ends being connected by a ring of bladin similar to the guide wheel of a turbine, w ereby a boringcad is formed.

In the drawing several ways of constructing the apparatus are shown.

Fig. 1 is a partial longitudinal section through the apparatus;

Fig. 2 a sectlon on the line 2-2in Fig. 1;

Figs. 3 and 4 show articular parts;

Fig. 5 is a partial ongitudinal section of the first alternative;

Fig. 6 is a section on the line 6-6 of Fig. 5;

Fig. 7 is a section on the line 7-7 of Fig. 5;

Fig. 8 is a partial longitudinal section of the second alternative.

Referring to Figs. 1 and 2, the apparatus consists of the outer tubes 1, 1 and an inner tube 2, arranged concentrically with the tubes 1, 1. The lower ends of the two vertical tubes 1 and 2 are connected together by a system of guide blading 3 forming a boring head.

The openings 4 in the blading are tangential and arranged sloping downwards, whereby a circular and somewhat downwardly directed motion is given to the pressure-water flowing through them, and thereby a similar motion to the abrasive medium carried with the water. The abrasive sand is, in consequence of its high specific gravity, thrown by centrifugal action against the side of the bore-hole W and grinds it out. In this manner the bore-hole is widened and deepened. As the boring process advances, the apparatus is lowered, and lengthening pieces are attached when necessary.

In order to protect the ends of tube 2 against any possible abrasion, its walls are thickened outwardly at 5; but it could also be protected by a jacket of resistant material, for example, abrasive material.

By the circular action of the pressurewater which carries the introduced mixture of mud and sand with it, a similar motion will also be caused in the abrasive material in the upper half of the blading 3; the inner walls of the tubes 2 at 9 and the blades of the blading are therefore liable to wear to a certain extent. The tube 2 may therefore also be thickened inwardly at 9, as shown in Figs. 3 and 4, and the ends of the conducting blading are formed somewhat projecting, whereby the sand is prevented from forcing its way behind the Whirl of Water formed by the issuing pressure-water.

Fig. 4 shows another alternative where the blading is constructed as a cone. The

blades in this case are less liable to wear, and, besides that, the injector or suction action of the abrasive mass will be increased.

In order to protect the guide blading 3 and the lower end of the pipe 2 better against wear from the sand forced in by the whirl of water caused by the pressure water flowing out, than by thickening them` the alternatives according to Figs. 5, 6 and 7 are fitted with a counter-current arrangement over the guide blading 3.

This counter-current device consists of a second row of blading 6 fitted to the tube 2, the inlet and outlet openings 7 and 8 in this blading being so arranged that a small quantity of pressure-water can enter the tube 2 at a somewhat lower velocity than the water passing through the blading 8, and partly in a contrary and partly 1n a radial direction. The effect of this counter or radial flow is to prevent a rotation of the abrasive medium flowing in above the blading 3, as at that spot the infiuence of the streams from the two rows of blading on the sand introduced is nil, and the sand is thrown away from the wall of the tube against the rock which is to be bored.

In Fig. 8 another alternative arrangement of the apparatus is shown. In order to protect the boring head from touching the bottom of the bore-hole and being damaged if the apparatus is lowered too quickly` the head is fitted adjustably in the tubes 10 and 11. The boring head here consists of two pieces of tubing 12 and 13 connected through the blading, these pieces of tube being arranged to slide watertight in the tubes 10 and 11 and connected with each other by the springs 14 fixe-d to the tube piece 12. In the neighborhood of the outer piece of tube 12, an electric warning signal arrangement S is provided. If the tube piece 12 should knock on the bottom of the bore-hole, a backward movement is caused, breaking the electric circuit and thereby actuating a signal for warning the attendants in charge of the boring operations.

In order that the piece of tube 13 with which the blading is firmly connected and which is most liable to be worn awa-y, can be inspected or replaced. it is arranged to be changed by its inner wall being turned over (16) so that a draw-tool can be attached in order to pull out the piece of tube. When drawing out the piece 13, the piece 12 will also be raised with it through the action of the springs 14 until the springs are forced back by the pipe 11 which serves as a stop and are thus brought away from the piece 13; the piece 12 then falls again and the piece 13 can be raised.

The method of using and working the described apparatus is as follows.

If a bore-hole is to be sunk, a hole, about 20 in. deep, for guiding the apparatus is first of all made by hand. The apparatus is then set in the hole and suspended by means (not shown) in such a manuel' that the boring head does not touch the bottom. The pressure-water is then introduced between the two tubes 1 and 2 and the abrasive material into the inner tube 2, also under pressure if desired. The pressure-water streaming out through the blading at great speed draws the abrasive material with it and gives the consequent mixture of water and abrasive material a circular motion. where by a tubular hollow is worn out of the rock which is to be bored. A core builds up inside the tube 2 and breaks and can be raised from time to time, whilst the borehole is widened and deepened through the mixture of sand and water acting at the same time tangentially and downwards, or through its centrifugal action. The material from the bore is washed out by the constant fiow of pressure-Water and comes to the surface; there the pressure-water is separated from the mud and abrasive material, and the latter can be used over again.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. The process of boring rock or the like which comprises introduclng water under pressure at high speed onto or over the place where the bore is being made, and introducing an abrasive substance at the same place, the pressure-Water and abrasive substance being conducted separately to the place where the bore is being driven.

2. The process of boring rock or the like which comprises separately conducting Water under pressure and an abrasive material to the place where the bore is being driven, and causing the pressure-water and abrasive material conjointly to effect the borin action at that place.

3. e process of boring rock or the like which comprises ejecting water at high speed onto or over the place where the bore is being made, and supplying an abrasive material at said place to cooperate with the ejected water in e'ecting the boring action, the su ply of abrasive material being indepen ent of the ejecting means for the water.

4. Apparatus for boring rock and the like comprismg an inner tuhe through which an abrasive material may be conducted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be oonducted to said place, and a boring head associated with said tubes having an o ning for admittn the pressure-water to t e abrasive material at the place where the bore is being driven.

5. Apparatus for boring rock and the like comprising an inner tube through which an abrasive material may be conducted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said tubes having an opening for admitting the ressure-water to the abrasive material at t e place where the bore is being driven, the sectional area of said opening bein smaller than the sectional area of flow t rough the water conducting space between the tubes.

6. Apparatus for boring rock and the like comprising an inner tube through which an abrasive material may be conducted to the place where the bore is being driven, an

outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said tubes having a plurality of openings for admitting the ressurewater to the abrasive material at t e place where the bore is being driven.

7 Apparatus for boring rock and the like comprislng an inner tube through which an abrasive material may be conducted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said tubes having a plurality of openin s for admitting the pressurewater to t e abrasive material at the place where the bore is being driven, said openings being inclined obliquely downward.

8. Apparatus for boring rock and the like comprising an inner tube through which an abrasive material may be conducted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said ktubes having a plurality of openings for admitting the pressurewater to the abrasive material at the place where the bore is being driven, said openings being inclined obliquely downward and arranged tangentially with respect to the axis of the tubes.

9. Apparatus for boring rock and the like comprising an inner tube through which an abrasive material may be conducted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said tubes having a plurality of circularly arranged turbine-like openings for admitting the pressure-water to the abrasive material at the place where the bore is being driven.

10. Apparatus for boring rock and the like comprising an inner tube throu h which an abrasive material may be con ucted to the place where the bore is being driven` an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said tubes having a urality of circulan-ly arranged turbineike openings for admitting the pressure-water to the abrasive material at the lace where the bore is being driven, the walls of the head in the vicinity of said openings being thickened.

11. Apparatus for boring rock and the like comprising an inner tube through which an abrasive material ma ybe conducted to the place where the bore 1s being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head` associated with said tubes having a lurality of circularly arranged turbineike openings for admitting the pressure-water to the abrasive material at the place where the bore is being driven, the walls of the head in the vicinity of said openings being thickened and the lower end of the inner tube projecting inwardly over said openings.

12.' Apparatus for boring rock and the like comprising an inner tube through which an abrasive material may be conducted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said tubes having a plurality of circularly arranged turbine-like openings for admittin the pressure-water to the abrasive materlal at the place where the bore is being driven, said boring head being cone-shaped.

13. Apparatus for boring rock and the like comprising an inner tube through which an abrasive material may be conducted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said place, and a boring head associated with said tubes having a plurality of circularly arranged turbine-like openings for admitting the pressure-water to the abrasive material at the place where the bore is being driven, there being provided above said openings a set of passages adapted to admit some of the pressure-water to the interior of the inner tube in a direction which is partly radially and partly contrary in direction to the direction of motion of the water issuing from said turbine-like openings.

14. Apparatus for boring rock and the like comprising an inner tube throu h which an abrasive material may be con ucted to the place where the bore is being driven, an outer concentric tube between which and the inner tube water under pressure may be conducted to said, lace, a boring head asf sociated with sais tubes having a plurallty of circularly arranged turbine-like openings for admittin the ressure-water to the abrasive materia at t e place where the bore is being driven, said boring head being slidably mounted with respect to said tubes, and a warning device adapted to be actuated by upward movement of the head with respect to the tubes.

15. Apparatus for boring rock and the like comprising an inner tube throu h which an abrasive material ma be con ucted to the place where the bore 1s bein driven, an outer concentric tube between w ich and the inner tube water under pressure ma be conducted to said lace, a boring ead associated with sais tubes having a plurality of circularly arranged turbine-like openings for admittin the ressure-water to the abrasive materia at t e place where the bore is being driven, said boring head comprising relatively slidable inner and outer tube pieces and connecting means for normally holding said tube pieces in operative relation, said means being releasable to permit withdrawalof the inner tube piece.

In testimony whereof I have atlixed my signature.

SCHAUB, OTTO. 

